Some Japanese numbers got released for real world driving on it.
2023 Toyota Prius w/ the 2.0L I4
Combined Mode: 28.6 km/L
City Mode: 26.0 km/L
Suburban Mode: 31.1 km/L
Highway Mode: 28.2 km/L
2023 Toyota Prius w/ the 1.8L I4 <-- Not offered here. Yet.
Combined Mode: 32.6 km/L - 13.9% higher than the 2.0L
City Mode: 29.9 km/L - 15% higher than the 2.0L
Suburban Mode: 37.3 km/L - 20.0% higher than the 2.0L
Highway Mode: 31.2 km/L - 10.6% higher than the 2.0L
That’s about 73 miles per gallon on the highway with the 1.8L version! Insane